Consolidated Statements of Operations (Parenthetical)	Dec. 31, 2021	Jul. 14, 2021
Income Statement [Abstract]
Common stock shares conversion ratio as part of offering pursuant to share based scheme	1.3163	1.3163

Common stock shares conversion ratio as part of offering pursuant to share based scheme.

No definition available.

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Namespace Prefix:	bcow_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant